In conventional clothes washing machines, either front loading or top loading, the spinner is rotatably mounted within the cabinet. A balancing system can be provided in the machine so as to counteract uneven or unbalanced loads in the spinner during the spin cycle. In the spin cycle, an exact balancing never actually takes place with respect to the axis of rotation of the rotating container. A radial force develops from this imbalance generating a moment about the bearings. The vector direction of this moment rotates with the spinner. This rotating force and moment cause oscillations and vibrations which must be substantially eliminated.
These oscillations and vibrations have been eliminated to some degree by active balancing systems which are continuous duty cycles for a pump valve combination that moves mass while a mass placement algorithm calculates the new unbalance. After this new unbalance is calculated, more mass is transferred resulting in a smaller unbalance. This process continues until the degree of unbalance is within a specified tolerance. Invariably, the serial process of computation and then mass transfer consumes a substantial amount of time. As the speed of the rotating unbalance increases, the magnitude of the required counterbalance mass decreases. Eventually, the magnitude of the required counterbalance mass approaches the resolution of the mass transfer devices.
It is therefore the principal objective of this invention to remedy the drawbacks indicated and to provide a method by which the tolerances and the time required to achieve those tolerances are reduced.
Another objective of the present invention is the provision of an improved method for balancing the spinner of a washing machine.
Another objective of the present invention is the provision of an improved washing machine wherein the balance system is such that the washing machine is virtually free from oscillations and vibrations caused by an unbalanced load.
These and other objectives will become apparent from the following description of the invention.